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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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58                                  ALASKAN GLACIER STUDIES
forest that grew in the ablation moraine had gone, much alder and cottonwood still remained. The destruction of neither the moraine nor the forest was complete, but the margin presented a far different appearance from that of 1905. Then the forest-bearing portion of the glacier margin was a moderately sloping embankment covered with forest verdure; in 1909 there were wooded patches interspersed with areas of barren moraine, and even with ice cliffs visible from a distance. In view of the rapidity with which the moraine was being removed from the ice in 1906 and the forest being destroyed, the fact that no more destruction had been accomplished-makes it difficult to believe that the period of advance and breakage lasted even into the summer of 1907. With cessation of motion, ablation in the low marginal areas would quickly bring about a sufficient degree of soil stability for vegetation already growing to maintain itself with little further destruction by undermining. However, that ablation was still proceeding rapidly in those parts of the glacier not protected by a deep ablation moraine was indicated by the volume of the Kwik River, which appeared to be even larger in 1909 than in 1906. That such a speedy ending of the 1905-6 advance, and the consequent rapid healing of the broken surface by ablation was not peculiar to the Marvine lobe of the Malaspina Glacier is made clear in later pages where other advancing glaciers are considered.
HAYDEN GIACIBB 1                        ,
This glacier has already been mentioned as one of the tributaries of the Malaspina Glacier, though contributing little ice to it. Heading on the western slopes of Mount Cook the Hayden Glacier flows as a broad, moderately-sloping valley glacier (PL XHI, B), with a width of 3 or 4 miles, and, on emergence from its mountain valley, expands to almost double that width, coalescing with the Marvine lobe of the Malaspina. A moderate recession would disconnect it from the Malaspina, giving it independent existence, such as Atrevida and Lucia Glaciers, once tributary to the Malaspina, now have. It is somewhat crevassed in places, and below the snow line, just west of Floral Pass, is bordered by lateral moraines, while on the expanded portion, outside the mountain, are several medial moraines and morainic swirls of interesting pattern. The amount of moraine on the surface increases toward the Marvine lobe, giving rise to many morainic ridges; but nowhere except along the margins is there a continuous cover of ablation moraine.
This glacier was partly crossed by the junior author in 1906 and observed and photographed from the western slopes of Floral Hills; and it was crossed and recrossed several times, and along several routes by the senior author in 1906. Travel across its surface in any direction was not difficult and it was evident that there had been no noteworthy change in condition since Russell crossed it in 1890. We did not get as far west as the Hayden Glacier in 1909 for the broken Lucia Glacier stood in the way, but we saw portions of its surface with field glasses in 1909 and 1910 and were convinced that it had not undergone any noteworthy change in the interval between 1906 and 1910. This negative result is interesting in view of the fact that Marvine Glacier, the next large glacier toward the northwest, and Lucia and Atrevida Glaciers, its large neighbors toward the southeast, have both felt the impulse of the earthquake advance. One may anticipate that its turn will soon come.
i For a fuller description, see Tarr, R. S., Professional Paper 64, U. S. Geol. Survey, 1909, pp. 81-88.